1. Technical Field
This invention relates to a decentralized radiocommunications system as set forth in the preamble of claim 1 and to a radio station therefor.
2. Discussion of Related Art
DE 39 08 940 A1 discloses a decentralized radiocommunications systems with a number of radio stations. Each of the radio stations has at least one neighboring radio station with which it is in direct radio communication. The prior-art radiocommunications system makes available several pairs of channels for duplex transmission between the radio stations. To ensure reliable radiocommunication, prior to the establishment of a radio link, each radio station checks all channels to determine whether they are free, and creates a so-called channel occupancy list. Then, a radio link is established to a neighboring radio station on a free channel. If the neighboring radio station is not a destination station but is to serve as a relay station, it will evaluate its channel occupancy list to establish a radio link to a further radio station. This makes it possible to establish so-called radio chains. In the radiocommunications system described in DE 39 08 940 A1, however, each radio station must check all channels prior to the establishment of a radio link, i.e., each station must include a scanning receiver. In addition, a radio chain can be established in the prior-art radiocommunications system only if a free pair of channels is found for each of the radio links, i.e., if several radio frequencies are available.